Video

Nevermind any relevant discussion on impedance matching. The Piezo is a super high Z device. It needs a ten meg input circuit, you are using much less than that. No wonder their is no bottom end. A JFET buffer with a 10 Mega ohm input resistor will work pretty good.

very nice content, good job

what happens if you connect the harp strings to electricity?

If you make each bridge support one string like a koto, you'll be able to re-tune between compositions or even in the course of a composition much more easily as well as making the instrument louder. Of course it will easily get knocked out of that tuning, but that seems a reasonable trade-off for the gain in function.

A 2GHz pentium goes fast enough to easily calculate waveforms like this in real time and still have bandwidth left over to play Tetris. This is what torpedoed the whole electronics hobby. It's good to see someone still into it.

Its always dubious meeting someone who is cleverer than i was.

Since you know the frequency of each string, you could use a pulse width modulator (PWM) to drive the coils instead of sensing them. You need a sensor on a guitar (eBow) to figure out what note is being played, but in a drone instrument like this it isn't necessary unless you re-tune it, but I think the PWM parts will take a voltage input so you could put a pot for each coil to tune the driver to each string. You'd still need the amplifier circuit but not the input coil.

Almost no tools ...just a workshop full of all kinds of different saws and drills and hardware etc...etc... lol

I appreciate your explaining of the electronic circuits! And I like the passion! You seem really fun! And clever, the robot on your channel page looks very advanced. Then, your "CZcams Clickbait" faces start appearing. :-( I've heard it still increases views, even though the person looks really dumb on the thumbnails. Well. It scares me away :'-D

The person who "reverse engineered" that e-bow LM386 schematic made some major mistakes. Amatuerish. 😑

What about programming a PWM signal from a bastardized motor controller, or some microcontroller? The program could drive notes or harmonics without simply constant droning. May be possible to drive two notes concurrently. The PWM signal could replace the input pickup entirely.

I remember playing against this guy in wii bowling

try piezo elements... they work both ways. and theres actually a huge range of different transducers available. you dont have to mount them at both ends the same way? a plain under-bridge strip pickup, and individual cylinders under the "fixed" end of the string... run a filter circuit on the feedback loop, random noise generator controlling frequency and bandwidth(q) so only one string pulls into resonance at any time... iunno... somewhere i have an old piezo based reverb unit... uses strips flexing to twist the spring somehow. bit fiddly! spring reverb use "torsional wave" transmission. reduces outside influences. seems unrelated but interesting to know... theres three waves in a string. transverse, beam, and torsional. they arent necessarily harmonically related! imho, its why certain scale lengths and string gauges work, whereas others dont... you can wriggle it up and down. the obvious "wave" of any stringed instrument. that itself breaks down into two components, XZ and YZ planes. one parallel to the bridge or "soundboard", one perpendicular. strings really "gyrate". you can bang on it end wise. the not so obvious wave at the speed of sound in the string itself reflecting end to end... and you can twist it. this is an interesting mode... theres other factors as well... placement of the pickups! stretch the poles of your pickup out with soft iron to be on both sides of the string, especially the exciters? but remember theres a nasty thing called "magnetic quench" when the fields TOO strong! that also may play a vital role in the overtone content... where the signal is being injected into the string... and thats why i prefer the piezo idea... can get it right in at the node of ALL harmonics, the fixed mount... a guitar pickup can always be mounted lengthwise, one per string... "single coil" humbuckers have really nice thin coils... i wound my own pickups years ago on bits of filed down hacksaw blade... worked quite well!

In my experience with the ebow, changing the position of the exciter coil along the string's length will accentuate certain harmonics.

Day Tripper !

Replace wooden bridge with steel it will conduct sound better. Then touch the output transducer to the metal bride. I mount mine thru a hole in the sound board,and touching the bridge. It will really come alive. I also use a piezo on the input . It resonates all my strings on my 3 string cbg.

Great project!

Other types of coils you can try are from a good sized relay! They are way bigger tho. But magnetics is weird the field is tuned to each application you want a concentrated field acting on the string. A speaker coil is more of a flat field to drive the whole diaphragm. In practice this is done by a double humbucker pickup one side is out other is input and i think you still take the signal out to your speaker.

Why did you lower the pickups when you could have raised the strings?

DUDE!! WTF! That SOUNDED AMAZING!!! God! I need 48 Hours a day pleaze!

you could prolly use a PET water bottle for the front of the box (tacked around the edge and shrunk with heat). Saw a man on YT who makes violins from "scrap materials," and two use thin plastic -- one a water bottle. But, seems like you're done, having found how to make it louder. Cool stuff!

eye - o - lee - an. not alien! lol

*******Reverberation NATURALLY could be achieved by placing 2 to 6 lengthy springs (tunable/tighten/loosenable at one end of anchor and placing the lot withing the Larger Sound Body of instrument. I've done this to a few of my Acoustic Guitar builds!. To also help this Journey look at the Science of vibrations of a string and how it breaks up into it's overtones etc. the best production to these vibrations are dead center between nut and bridge(half distance of string). Guitars are obviously limited of it's strength due to the fretboard double octave being in the way of play area. Of course, until we guitarists develop a sustaining system that can utilize a miniaturized and amplified DRIVER P.U. via Utilizing the Fret as the P.U. Slug which is located half distance between both the Nut and the Bridge. Lastly....for any Guitarist the Driver response in such a setup could pose problematic when playing Further up the neck and beyond the double octave area!*******

I got a bag of Piezos, soldered those to cables just like that, and it worked well on the drumkit and a 1995 Yamaha mixer. We attached the pads with duct tape to the drums.

You could use a long wire antenna to harvest stray RF to possibly power this thing out in nature without a battery. I'm not sure what kind of wattage you need for it to properly function but if you want to see an example of what I mean, this guy powers some LEDs using nothing but a wire laying in a park: czcams.com/video/yqljaKjKjd4/video.html

Ah, the sound of gridlocked, rush hour traffic right in my own window you say? And all it costs is tripling my HVAC bill? Where do I sign up?

Why the fuck is it so hard to find a video of one of you aeolian nerds playing the fuckin thing? I don't care about the history or your project, I just want to see somebody play it, just play the fucking thing! I went down this path to figure out why the harmonica is referred to as a harp, so I just found out about that this thing exists in the first place and all I want to see is anyone play it. I also didn't read the title, so my fault I guess.

you are incredible...this is amazing

Excellent stuff, great presentation and a really underrated channel in general. Do you know Cylob's singing synthesis stuff?

Driving the output with a square wave means you can only really get the loudest string at any one time, but using a proper audio amplifier that isn’t saturated should be able to keep the nuance of lower loudness strings all summed onto one another. Also you can just turn guitar pickups sideways.

When doing those inductor filling calculations, I ditch the “proportionality” and use the proper constants. Not only does the bobbin have a maximum cross section for wire, but also a maximum power dissipation. For a guitar pickup maybe that’s 5W. Then knowing my voltage, I figure out what total resistance I’ll need to meet for that power consumption, and calculate the number of turns and of what diameter to meet that based off the cross sectional area of windings I have to work with. Then I design a driving stage, in this case it can be any old half-bridge, be it with FETs, a monolithic L293/L298, or a BJT totem pole. Gotta include the voltage dropout in the above calculations though. Does having a permanent magnet in the output coil actually matter? It’s necessary in the input coil since you need it to induce a magnetic field in the string to detect its motion, but here you’re already producing a magnetic field with the output coil.

Now put a CD4046 after the comparator but before the half-bridge. If you use the standard type-2 phase comparator, you’ll get no phase shift and can set the frequency division with counters. But if you use the type-1 phase comparator, the frequency that it locks to will be more dependant on the VCO, and it will likely lock to harmonics. Putting a potentiometer as the VCO’s resistor will help you control what harmonic it locks onto. Guitar pickups are designed for magnetic reception, less so for actually stimulating the strings. The strings would be better stimulated by an inductor with an iron or ferrite core, as opposed to a rare earth magnet core.

Piezo ceramics have very prominent and wide peak at the resonance frequency that depends on their physical characteristics (size etc.) and what's more, if you deform the disc, unless the energy stored has a way to dissipate, it'll stay deformed until the stored energy will leak away naturally. Thus you must have a resistor, or some other way for energy to dissipate, at the output of the disc or it has no low frequency response to speak of.

Here's an idea: some strings have a significant amount of nickel, right? If you pass the string through the center of a coil, you could use the magnetostrictive effect as either a pickup or as a driver/actuator. The same could perhaps be done with a tuning peg as the "core" of a coil.

Awesomesauce my friend! I feel your struggles - a few weeks ago I rewound the coil on a balanced armature speaker/sound powered phone, matching the original as best I could. Fixing that thing had me missing the PCB rework I used to do under a microscope.

Eee! I'm unreasonably excited to have stumbled upon this! I bought a 3d printer expressly to do things like this- I don't really plan to build a computerized version though, unless I make it a midi module later. Edit: I mean that I plan on making it fully mechanical- you've already done the hard work with the midi part too!

Hating on Thoreau, based upon 2024's views of what men _should've_ been like in the first half of the 19th century, is not a good look. He may have had his flaws, but compared to most men back then, he was an original thinker and something of a renaissance man.

COILS have polarity???

The aeolis harps I heard about were mounted on roofs.

Remember that time Thoreau had a vacation at his parent's friends summer cottage, just down the road from his own home, where he still went to do his laundry, then wrote a book about it like it was one man conquering the wilderness? Remember that other time he wrote an essay about how much he loves walking in the outdoors because nobody is there, and if anyone were there, anyone at all, one single person, any individual person in the outdoors would completely ruin the outdoors for him.

i wonder if you could make the sound board out of a very thin sheet of aluminum or steel and then you could use circuitry and inductance to create a sustainer out of the soundboard itself (i have no knowledge on any of this so dont shot me if im wildly off in lalaland with the idea)

Thanks for making this!

the last experiment was "disappointing" (in the sense that the response was not A + B) but highly effective to demonstrate your point

Wow awesome video! I'd love to get one of those sustainer circuit kits.

Knew there'd be an lm386 in there somewhere 😂

dont use a 5v reg, use a buck

I don understand that schematic where is the input ? how does it sense strings ?

Great stuff, nicely packaged sustainer circuit, I have working on similar things.

I will be shaving my buzzers down, to stop the buzzing ! My two heaviest wound strings are terrible for it.

This so similar to something I have working on, I am using reverse polarity for high octave and graphic EQ for overtones. 12 volt power for the driver amps. 9 volt powered pre amps, one of each for each string. czcams.com/video/lgvu-S_xDEo/video.htmlsi=8qRf2WNrUWP_5AZj